There’s no reason to assume that only one section of Limacella exists in southern California. This material has no membranous annulus that I can see; hence, if it is a Limacella, then it wouldn’t be in section Amanitellae (which has a membranous, non-slimey partial veil and a dry stem). However, it is amazing to me that you are finding such taxa in the current drought. Are you getting rain?